timeline item
Results
Here is the information we have
on the item you selected
More like this
NEW SEARCH
| |
sign up for our newsletter
© 2017 Engineering Timelines
engineering-timelines@severalworld.co.uk
engineering timelines
explore ... how   explore ... why   explore ... where   explore ... who  
home  •  NEWS  •  search  •  FAQs  •  references  •  about  •  sponsors + links
Bollinhurst Dam
south of Disley, Cheshire
associated engineer
George Henry Hill
date  circa 1872
era  Victorian  |  category  Dam/Reservoir  |  reference  SJ972836
ICE reference number  HEW 1151
Bollinhurst is a zoned earth dam, built under the terms of the Stockport District Waterworks Act 1863. It's valve shaft is located in the reservoir behind it — an early example of what is now common practice.
The dam is located on relatively high ground, just south of Disley, bordering on Lyme Park. The drawings for it are dated March 1871. It measures some 245m long and is 17m high. The crest of the dam is 4.6m wide. A parapet wall was added along this crest at some later date.
Zoned earth dams consist of areas of distinct materials. In this case, concrete, clay and stone have been used. A cross section through the dam would reveal a triangular shape, with a 3:1 slope on the upstream side (in the reservoir) and another slope on the downstream side, both meeting at the crest, which is the highest point of the dam.
Earth dam construction begins with the digging of a cutoff trench running the full length which is then filled in with impervious material, in this case concrete. The idea is to stop seepage from the reservoir under the dam. At Bollinhurst, the outlet tunnel from the valve shaft runs through the concrete cutoff.
Above the cutoff, the dam has a puddle clay core with selected fill used either side of it. On the upstream side, an additional wide layer of clay forms a berm (or ledge) against the slope at the foot of a 600mm thick layer of stone pitching.
The valve shaft, located in the reservoir, is reached by a long access bridge.
Research: PD
Location

Bollinhurst Dam